[libcamera-devel] [PATCH v3 3/5] android: Add CameraHalConfig class
Jacopo Mondi
jacopo at jmondi.org
Tue Mar 30 16:21:11 CEST 2021
Add a CameraHalConfig class to the Android Camera3 HAL layer.
Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
README.rst | 2 +-
src/android/camera_hal_config.cpp | 407 ++++++++++++++++++++++++++++++
src/android/camera_hal_config.h | 36 +++
src/android/meson.build | 2 +
4 files changed, 446 insertions(+), 1 deletion(-)
create mode 100644 src/android/camera_hal_config.cpp
create mode 100644 src/android/camera_hal_config.h
diff --git a/README.rst b/README.rst
index 7a98164bbb0a..f68d435196de 100644
--- a/README.rst
+++ b/README.rst
@@ -88,7 +88,7 @@ for tracing with lttng: [optional]
liblttng-ust-dev python3-jinja2 lttng-tools
for android: [optional]
- libexif libjpeg
+ libexif libjpeg libyaml
Using GStreamer plugin
~~~~~~~~~~~~~~~~~~~~~~
diff --git a/src/android/camera_hal_config.cpp b/src/android/camera_hal_config.cpp
new file mode 100644
index 000000000000..b109ad24e1d1
--- /dev/null
+++ b/src/android/camera_hal_config.cpp
@@ -0,0 +1,407 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Google Inc.
+ *
+ * camera_hal_config.cpp - Camera HAL configuration file manager
+ */
+#include "camera_hal_config.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <yaml.h>
+
+#include <hardware/camera3.h>
+
+#include "libcamera/internal/file.h"
+#include "libcamera/internal/log.h"
+
+using namespace libcamera;
+
+LOG_DEFINE_CATEGORY(HALConfig)
+
+namespace {
+
+std::map<std::string, CameraProps> cameras;
+
+std::string parseValue(yaml_parser_t *parser)
+{
+ yaml_token_t token;
+
+ /* Make sure the token type is a value and get its content. */
+ yaml_parser_scan(parser, &token);
+ if (token.type != YAML_VALUE_TOKEN) {
+ yaml_token_delete(&token);
+ return "";
+ }
+ yaml_token_delete(&token);
+
+ yaml_parser_scan(parser, &token);
+ if (token.type != YAML_SCALAR_TOKEN) {
+ yaml_token_delete(&token);
+ return "";
+ }
+
+ char *scalar = reinterpret_cast<char *>(token.data.scalar.value);
+ std::string value(scalar, token.data.scalar.length);
+ yaml_token_delete(&token);
+
+ return value;
+}
+
+std::string parseKey(yaml_parser_t *parser)
+{
+ yaml_token_t token;
+
+ /* Make sure the token type is a key and get its value. */
+ yaml_parser_scan(parser, &token);
+ if (token.type != YAML_SCALAR_TOKEN) {
+ yaml_token_delete(&token);
+ return "";
+ }
+
+ char *scalar = reinterpret_cast<char *>(token.data.scalar.value);
+ std::string key(scalar, token.data.scalar.length);
+ yaml_token_delete(&token);
+
+ return key;
+}
+
+int parseValueBlock(yaml_parser_t *parser)
+{
+ yaml_token_t token;
+
+ /* Make sure the next token are VALUE and BLOCK_MAPPING_START. */
+ yaml_parser_scan(parser, &token);
+ if (token.type != YAML_VALUE_TOKEN) {
+ yaml_token_delete(&token);
+ return -EINVAL;
+ }
+ yaml_token_delete(&token);
+
+ yaml_parser_scan(parser, &token);
+ if (token.type != YAML_BLOCK_MAPPING_START_TOKEN) {
+ yaml_token_delete(&token);
+ return -EINVAL;
+ }
+ yaml_token_delete(&token);
+
+ return 0;
+}
+
+int parseCameraLocation(CameraProps *cameraProps, const std::string &location)
+{
+ if (location == "front") {
+ cameraProps->facing = CAMERA_FACING_FRONT;
+ } else if (location == "back") {
+ cameraProps->facing = CAMERA_FACING_BACK;
+ } else if (location == "external") {
+ cameraProps->facing = CAMERA_FACING_EXTERNAL;
+ } else {
+ cameraProps->facing = -EINVAL;
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+int parseCameraProps(yaml_parser_t *parser, const std::string &cameraID)
+{
+ int ret = parseValueBlock(parser);
+ if (ret)
+ return ret;
+
+ /*
+ * Parse the camera properties and store them in a cameraProps instance.
+ *
+ * Add a safety counter to make sure we don't loop indefinitely in case
+ * the configuration file is malformed.
+ */
+ unsigned int sentinel = 100;
+ CameraProps cameraProps{};
+ bool blockEnd = false;
+ yaml_token_t token;
+
+ do {
+ yaml_parser_scan(parser, &token);
+ switch (token.type) {
+ case YAML_KEY_TOKEN: {
+ yaml_token_delete(&token);
+
+ /*
+ * Parse the camera property key and make sure it is
+ * valid.
+ */
+ std::string key = parseKey(parser);
+ std::string value = parseValue(parser);
+ if (key.empty() || value.empty())
+ return -EINVAL;
+
+ if (key == "location") {
+ ret = parseCameraLocation(&cameraProps, value);
+ if (ret) {
+ LOG(HALConfig, Error)
+ << "Unupported location: "
+ << value;
+ return -EINVAL;
+ }
+ } else if (key == "rotation") {
+ cameraProps.rotation = strtoul(value.c_str(),
+ NULL, 10);
+ if (cameraProps.rotation < 0) {
+ LOG(HALConfig, Error)
+ << "Unknown rotation: "
+ << cameraProps.rotation;
+ return -EINVAL;
+ }
+ } else if (key == "model") {
+ cameraProps.model = value;
+ } else {
+ LOG(HALConfig, Error)
+ << "Unknown key: " << key;
+ return -EINVAL;
+ }
+ break;
+ }
+ case YAML_BLOCK_END_TOKEN:
+ blockEnd = true;
+ /* Fall-through */
+ default:
+ yaml_token_delete(&token);
+ break;
+ }
+
+ --sentinel;
+ } while (!blockEnd && sentinel);
+ if (!sentinel)
+ return -EINVAL;
+
+ cameraProps.valid = true;
+ cameras[cameraID] = cameraProps;
+
+ return 0;
+}
+
+int parseCameras(yaml_parser_t *parser)
+{
+ int ret = parseValueBlock(parser);
+ if (ret) {
+ LOG(HALConfig, Error) << "Configuration file is not valid";
+ return ret;
+ }
+
+ /*
+ * Parse the camera properties.
+ *
+ * Each camera properties block is a list of properties associated
+ * with the ID (as assembled by CameraSensor::generateId()) of the
+ * camera they refer to.
+ *
+ * cameras:
+ * "camera0 id":
+ * key: value
+ * key: value
+ * ...
+ *
+ * "camera1 id":
+ * key: value
+ * key: value
+ * ...
+ */
+ bool blockEnd = false;
+ yaml_token_t token;
+ do {
+ yaml_parser_scan(parser, &token);
+ switch (token.type) {
+ case YAML_KEY_TOKEN: {
+ yaml_token_delete(&token);
+
+ /* Parse the camera ID as key of the property list. */
+ std::string cameraId = parseKey(parser);
+ if (cameraId.empty())
+ return -EINVAL;
+
+ ret = parseCameraProps(parser, cameraId);
+ if (ret)
+ return -EINVAL;
+ break;
+ }
+ case YAML_BLOCK_END_TOKEN:
+ blockEnd = true;
+ /* Fall-through */
+ default:
+ yaml_token_delete(&token);
+ break;
+ }
+ } while (!blockEnd);
+
+ return 0;
+}
+
+int parseEntry(yaml_parser_t *parser)
+{
+ int ret = -EINVAL;
+
+ /*
+ * Parse each key we find in the file.
+ *
+ * The 'cameras' keys maps to a list of (lists) of camera properties.
+ */
+
+ std::string key = parseKey(parser);
+ if (key.empty())
+ return ret;
+
+ if (key == "cameras") {
+ ret = parseCameras(parser);
+ } else
+ LOG(HALConfig, Error) << "Unknown key: " << key;
+
+ return ret;
+}
+
+int parseConfigFile(yaml_parser_t *parser)
+{
+ yaml_token_t token;
+ int ret = 0;
+
+ yaml_parser_scan(parser, &token);
+ if (token.type != YAML_STREAM_START_TOKEN) {
+ LOG(HALConfig, Error) << "Configuration file is not valid";
+ yaml_token_delete(&token);
+ return -EINVAL;
+ }
+ yaml_token_delete(&token);
+
+ yaml_parser_scan(parser, &token);
+ if (token.type != YAML_BLOCK_MAPPING_START_TOKEN) {
+ LOG(HALConfig, Error) << "Configuration file is not valid";
+ yaml_token_delete(&token);
+ return -EINVAL;
+ }
+ yaml_token_delete(&token);
+
+ /* Parse the file and parse each single key one by one. */
+ do {
+ yaml_parser_scan(parser, &token);
+ switch (token.type) {
+ case YAML_KEY_TOKEN:
+ yaml_token_delete(&token);
+ ret = parseEntry(parser);
+ break;
+
+ case YAML_STREAM_END_TOKEN:
+ ret = -ENOENT;
+ /* Fall-through */
+ default:
+ yaml_token_delete(&token);
+ break;
+ }
+ } while (ret >= 0);
+
+ if (ret && ret != -ENOENT)
+ LOG(HALConfig, Error) << "Configuration file is not valid";
+
+ return ret == -ENOENT ? 0 : ret;
+}
+
+} /* namespace */
+
+std::string CameraHalConfig::findFilePath(const std::string &filename) const
+{
+ static std::array<std::string, 2> searchPaths = {
+ LIBCAMERA_SYSCONF_DIR,
+ LIBCAMERA_DATA_DIR,
+ };
+
+ if (File::exists(filename))
+ return filename;
+
+ std::string root = utils::libcameraSourcePath();
+ if (!root.empty()) {
+ std::string configurationPath = root + "data/" + filename;
+ if (File::exists(configurationPath))
+ return configurationPath;
+ }
+
+ for (std::string &path : searchPaths) {
+ std::string configurationPath = path + "/" + filename;
+ if (File::exists(configurationPath))
+ return configurationPath;
+ }
+
+ return "";
+}
+
+FILE *CameraHalConfig::openFile(const std::string &filename)
+{
+ const std::string filePath = findFilePath(filename);
+ if (filePath.empty()) {
+ LOG(HALConfig, Error)
+ << "Configuration file: \"" << filename << "\" not found";
+ return nullptr;
+ }
+
+ LOG(HALConfig, Debug) << "Reading configuration file from " << filePath;
+
+ FILE *fh = fopen(filePath.c_str(), "r");
+ if (!fh) {
+ int ret = -errno;
+ LOG(HALConfig, Error) << "Failed to open configuration file "
+ << filePath << ": " << strerror(-ret);
+ return nullptr;
+ }
+
+ return fh;
+}
+
+/*
+ * Open the HAL configuration file and validate its content.
+ * Return 0 on success, a negative error code otherwise
+ */
+int CameraHalConfig::open()
+{
+ yaml_parser_t parser;
+ int ret = yaml_parser_initialize(&parser);
+ if (!ret) {
+ LOG(HALConfig, Fatal) << "Failed to initialize yaml parser";
+ return -EINVAL;
+ }
+
+ FILE *fh = openFile("camera_hal.yaml");
+ if (!fh)
+ return -ENOENT;
+
+ yaml_parser_set_input_file(&parser, fh);
+ ret = parseConfigFile(&parser);
+ fclose(fh);
+ yaml_parser_delete(&parser);
+ if (ret)
+ return ret;
+
+ for (const auto &c : cameras) {
+ const std::string &cameraId = c.first;
+ const CameraProps &camera = c.second;
+ LOG(HALConfig, Debug) << "'" << cameraId << "' "
+ << " model: " << camera.model
+ << "(" << camera.facing << ")["
+ << camera.rotation << "]";
+ }
+
+ return 0;
+}
+
+const CameraProps &CameraHalConfig::cameraProps(const std::string &cameraID) const
+{
+ static CameraProps empty;
+
+ const auto &it = cameras.find(cameraID);
+ if (it == cameras.end()) {
+ LOG(HALConfig, Error)
+ << "Camera '" << cameraID
+ << "' not described in the HAL configuration file";
+ return empty;
+ }
+
+ return it->second;
+}
diff --git a/src/android/camera_hal_config.h b/src/android/camera_hal_config.h
new file mode 100644
index 000000000000..5491a12fdffd
--- /dev/null
+++ b/src/android/camera_hal_config.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Google Inc.
+ *
+ * camera_hal_config.h - Camera HAL configuration file manager
+ */
+#ifndef __ANDROID_CAMERA_HAL_CONFIG_H__
+#define __ANDROID_CAMERA_HAL_CONFIG_H__
+
+#include <string>
+
+class CameraProps
+{
+public:
+ CameraProps()
+ : valid(false) {}
+
+ int facing;
+ std::string model;
+ unsigned int rotation;
+
+ bool valid;
+};
+
+class CameraHalConfig
+{
+public:
+ int open();
+ const CameraProps &cameraProps(const std::string &cameraID) const;
+
+private:
+ std::string findFilePath(const std::string &filename) const;
+ FILE *openFile(const std::string &filename);
+};
+#endif /* __ANDROID_CAMERA_HAL_CONFIG_H__ */
+
diff --git a/src/android/meson.build b/src/android/meson.build
index 8e7d07d9be3c..c0ede407bc38 100644
--- a/src/android/meson.build
+++ b/src/android/meson.build
@@ -3,6 +3,7 @@
android_deps = [
dependency('libexif', required : get_option('android')),
dependency('libjpeg', required : get_option('android')),
+ dependency('yaml-0.1', required : get_option('android')),
]
android_enabled = true
@@ -41,6 +42,7 @@ android_hal_sources = files([
'camera3_hal.cpp',
'camera_hal_manager.cpp',
'camera_device.cpp',
+ 'camera_hal_config.cpp',
'camera_metadata.cpp',
'camera_ops.cpp',
'camera_stream.cpp',
--
2.30.0
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